摘要
母材与钎缝界面处的金属间化合物会降低MnCuAl阻尼合金与430不锈钢钎焊接头的结合强度,进而降低焊接结构的使用性能。采用在430不锈钢表面电镀Ni层后再进行钎焊的方法对有害的金属间化合物进行抑制,同时探究不同厚度Ni层对接头组织、金属间化合物的影响规律和机理。结果表明,镀Ni层与基体界面处无明显缺陷,镀Ni层能够与430SS母材良好结合。对于钎焊接头,未镀Ni时,在430SS侧界面处分布着γ-(Fe,Mn)固溶体层,在两侧的反应层与钎缝中心区之间均存在连续分布的IMC,且伴随着钎剂残留;电镀8μm Ni层时,焊后镀Ni层完全溶解,在430SS侧界面处仍分布着γ-(Fe,Mn)固溶体层,但接头中金属间化合物消失,且只有极少数钎剂残留;镀层为20μm时,焊后在430SS侧有一层残余镀Ni层,未发现γ-(Fe,Mn)固溶体层,金属间化合物消失,且未见钎剂残留。分析认为,当镀层厚度分别为8μm、20μm时,Ni层分别是通过合金化作用、阻隔作用抑制了金属间化合物的生成。
Intermetallic compounds(IMCs)distributed at the interface reduce the bonding strength of MnCuAl alloy/430 stainless steel(430SS)brazed joints,and then reduce the performance of welding structure.Ni layer is electroplated on 430SS surface to inhibit the formation of IMC in the joint,then the effect and mechanism of Ni layer with different thickness on joint structure and IMC are investigated.The results show that there is no obvious defect at the interface between the Ni plating and the substrate,and the Ni plating can be well combined with the 430SS substrate.For the brazed joint without Ni plating,γ-(Fe,Mn)solid solution layer is distributed at the interface of the 430SS side,and there are continuous distribution IMCs between the reaction layer and the center of the brazing seam on both sides,accompanied by the brazing flux residue.When 8μm Ni layer is electroplated,the Ni layer completely dissolves after welding,γ-(Fe,Mn)solid solution layer is still distributed at the interface of the 430SS side,but IMCs disappeare and only a few brazing flux remaines.When the plating is 20μm,there is a residual Ni plating layer on the 430SS side after welding,noγ-(Fe,Mn)solid solution layer is found,IMCs disappeare,and no residue of brazing flux is observed.It is concluded that Ni plating can inhibit the formation of IMCs by alloying and blocking when its thickness is 8μm and 20μm respectively.
作者
张明月
张民安
胥永刚
张松
ZHANG Mingyue;ZHANG Min'an;XU Yonggang;ZHANG Song(Chengdu Industry and Trade College,Chengdu Technician College,Chengdu 611731,China;China Railway Materials Track Technology Service Group Co.,Ltd.,Chengdu 610031,China;Materials Science and Engineering College,Southwest Jiaotong University,Chengdu 610031,China)
出处
《电焊机》
2023年第4期103-111,共9页
Electric Welding Machine
基金
中央高校基本科研业务费科技创新项目(2682017CX073)。
